1. Field of the Invention
This invention relates to the precision and variable angle attachment between two waveguide components, for example the transition between a feed waveguide or transmitter output and a dual reflector antenna feed assembly. More particularly, the invention relates to a cost effective feed transition assembly with quick tool-less initial mounting and widely variable connection angle alignment features.
2. Description of Related Art
Microwave antennas commonly have a feed assembly linked to a transmitter or receiver by a waveguide. To minimize signal degradation, the waveguide components are precision formed to create closely aligned and gap free interconnections. An aperture in the waveguide signal path may be aligned to select between vertical and horizontal polarization by alternating the aperture orientation by 90 degrees. In addition to primary orientation for a desired polarization, a fine tuning ability is desirable to enable optimizing the selected polarization.
Prior dual reflector microwave antennas have used an aperture slip ring with a plurality of bolt holes, each bolt hole in the form of an arc shaped slot to permit fine adjustment of the selected aperture angle. This configuration has three main disadvantages. First, at least one of the plurality of bolts required to attach the aperture need to be inserted and threaded before the aperture becomes self-supporting. Seemingly simple mechanical operations of this type are made much more difficult when they must be performed in exposed locations such as high atop a radio tower. Second, the assembly is relatively expensive to manufacture, because the plurality of arc shaped bolt slots require complex machining capabilities. Also, the overall number of required separate components is significant, increasing a drop hazard during installation and maintenance. Third, to maintain the strength of the component, the arc shaped bolt holes have a minimal angular adjustment range. To change the angle 90 degrees from vertical to horizontal polarization, or vice versa, the entire assembly must be removed, rotated and again supported while the initial bolt(s) are re-inserted and tightened.
Alternatively, a slip ring separate from the aperture has been used, adding additional costs and introducing additional potential failure points to the overall system while maintaining the drawbacks described hereinabove.
Competition within the communications component and or systems industry has focused attention on structural integrity, materials and manufacturing operations costs. Also, ease of installation and service is a growing component and or system selection consideration.
Therefore, it is an object of the invention to provide an apparatus that overcomes deficiencies in the prior art.